A gate valve is usually defined as a valve which is used as a gate in the way of fluid in a pipe with the help of disks or wedges. Mostly gate valves are used in a pipe or whole piping system to control the flow of water through it.

A gate valve is usually in two positions i.e., completely opened or completely closed. When the gate valve is completely open then its disk is fully removed from the passage of water so that water could flow without any hindrance. But if the gate valve is completely closed then the disk is in the passage of the water so that flow of water can be stopped.

Types of gate valves

There are many types of gate valves, following are some of them:

• Slurry gate valve
• Butterfly valve
• Lined butterfly valve
• Knife gate valve
• Solid wedge gate valve
• Flexible wedge gate valve
• Split wedge gate valve
• Parallel disk gate valve

Purpose of a gate valve

Purpose of a gate valve (mostly slurry gate valve) is to provide a completely opened passage for the flow of water or any fluid as it is available in completely opened or completely closed positions. A slurry valve usually consists of wheel, gland, spindle, disc and a seat. As slurry gate valve is available in completely opened or closed positions it protects the pipe from erosion, cavities and turbulences in the passage of flow of fluid.

Butterfly valve as its name implies is butterfly like in shape and also used to facilitate the flow of water in a pipe or in a whole pipe line system.

Lined butterfly valve in australia is usually lined with rubber or anti resistant to corrosion material which help out the butterfly valve in its proper functioning.

Knife gate valve provides very high rate of flow as it is designed as bidirectional wafer design.

Mostly used gate valve is the solid wedge gate valve due to its simplicity and strength. It is mostly used in turbulent flow. It is suitable for every type of fluids and also it can be fitted or installed in any position according to our need. It should not be used in high temperature because the chances of leakage are much high in this type of Its valve. Its performance is highly affected by thermal expansion and inflexible

In flexible wedge gate valve, there is a cut on its perimeter. This cut, however, provides less flexibility but also help out in retaining strength.

Types of gate valve due to discs

• Solid wedge
• Split wedge
• Parallel disc
• Flexible disc

Types of gate valve due to body bonnets

• Welded bonnet
• Bolted bonnet
• Screwed bonnet

Types of gate valve due to stem movement:

• Rising stem type
• None rising stem type